Catheters are commonly used in vascular procedures. The catheter is threaded through the vasculature to a treatment site and treatment is delivered to or applied at the site. The treatment can take many forms, but a common treatment includes delivery of an implantable stent that may be collapsed or compressed to a low profile during delivery. Other catheterization treatments include the delivery of non-collapsible devices that have a relatively large transverse cross section. In certain of these non-collapsible implant devices it is undesirable to provide a passage through the device to accommodate medical guidewires or the like to assist in delivery of the device. For example, it is undesirable to design a battery for a wireless implantable pacemaker wherein the battery has a through hole to accommodate a guidewire.
Implantable devices that cannot be tracked concentrically over a guidewire are typically carried inside a sheath or catheter and are pushed out of the catheter open distal end by an elongate element such as a flexible rod slidably disposed in the lumen of the catheter. Especially in delivery systems where the catheter open end is necessarily large enough to accommodate the profile of the non-collapsible implant being delivered, the distal end of the catheter distal end can get caught on vascular tissue or can be misdirected into branch vessels, resulting in undesirably extending the clinical time required to deliver the implant. Therefore, it would be desirable to provide an implant delivery system that overcomes the aforementioned and other disadvantages.